Spring suspension of vehicles



1,633,933 June 28 1927' F. s. FARNswoRTH 3 SPRING SUSPENSIQN 0F VEHICLES med Dec. 5, 1923 2 sheets-snaai 1 June 28', 1927. 1,633,933 v v F. S. FARNSWORTH SPRING SUSPENSION OF- VEHICLES Filed Deo. 5,'1923 I 2 sheets-sheer 2 l L w i .Il v v I b21/azz @c i' masia- 01179 Patented June 28, 1927.

UNHTED vsiraresv 1,633,933 PATENT oFF'ics;

FRANK SMEDLEY FA'RNSWORTH, 'or LONDON, ENGLAND.

SPRING sUsrENsroN vo1 VEHICLES.

Application led December 5, 1923, Serial No. 678,743, and in Great Britain December 15,1922'.

My invention relates to the `spring suspension of vehicles. f

An object of my invention is to provide an improved spring suspension which will allow the wheels mounted on the ends of an axle to move vertically or 'approximately vertically without seriously disturbing the level of the axle, or whereby. in other words, the axle will retain the horizontal position when either wheel moves vertically in passing over an obstacle. To robtain this result it follows that each wheel must be sprung separately, andthat the flexion of any one spring or set of springs governing the action of one wheel must not be communicated to the springing arrangements of the other .wheel This result is of course impossible with the ordinary solid type of axle.

Another result obtained from the use of my improved suspension is the considerable reduction in the amount of unsprung weight. By the usual methods of vehicle suspension the springs are mounted direct on to the axles, and the chassis or framework carrying the engine and transmission gear (in a motor car) and bodywork is in turn .secured to the springs. By this construction any part of the vehicle. mounted beneath the springs is totally unsprung ex-` cept for the cushioning veect derived from the tyres. By. the use of the improved suspension the weight of the axles and springsV is fully sprung and the actual unsprung weight77 is reduced to little moreV than the weight of the wheels. Also, the springs are relieved of all side and drivingv stresses, their sole duty being to absorb shocks and vibration.

The invention refers to-spring suspension systemsof the kind in which it hasbeen proposed to mount the. road wheels on crank arms adapted to pivot on the ends of axles or on the chassis or body of the vehicle against the action of springs, each wheelbe ing sprung separately and adapted to move relatively to said `chassis or body independently of the other road wheels. In various constructions of the known systems it has' been proposed to mount the crank arms on axles or on short sleeves mounted to rotate in bearings provided on' the side members of thechassis or body, to provideload-carrying and rebound springsr of different strengths, and to connect crankl arms carrying the 1oa'cl v wheels directly to loadcarrying springs. f

bearings on said chassisor'body, and each of .said sleeves extends'half' the length of said axle, rod or tube, or approximately so, and is free to turn independently'on the axle,

rod or tube, and in itsy corresponding bearing. Another feature of the invention consists in that crank, arms of different lengths and provided on the sleeve of each wheel may be operatively connected to loadcarrying orv suspension springs and to rebound or reactio'nspr'ings of diii'erent strengths Y. Y

My invention will now be described with reference to the accompanying diagrammatic drawings, in which Figure I is a side elevation illus't'ra'ting'a` suitable manner of applying my invention to the front axle of amotor carchassis, and Figure 2 isa parts'ectional planl of the suspension' shown inFigure l. l Y

Figure 3 is a side elevation showing a conA- venient applicationl of myk invention to the rear axle of a motor car chassis, and' Figure 4 Ais a part sectional planof the suspension of Figure 3.

Fig. 5 is a; sectional view illustrating a modilication.A

Thus, in a suitable manner of carrying out my invention', and dealing with the front axle 'rst asjshown in Figures 1 and 2, I employ.

desired, the tie' rod c may be eliminated as illustrated in Figure 5. The sleeves b. are a working iit on the tube a and are adapted to rotate thereon. At the outer ends of the sleeves b are mounted crank-arms Z which are integral with Vor securedy onlthe sleeves, and are ofsuitable'length to carry the road wheels" Such as by means of stub axles. The rod or tube ai carrying the sleevesv Z2 andthe crankarms cl is secured to the framework or side members e of the vehicle chassis by bearings f formingparts of, or fixed to, the said side members; the journals g working in the bearings f are formed at theV outer ends of the sleeves Z) and as close as convenient to the crank-arms d carrying the road wheels. lt must be understood that the sleeves Z) are free to rotate in thevbearings f. A

On eachv sleeve Z), and as close as convenient to the inner side of the corresponding bearing f, is mounted another crank-arm 7L which is integral with or fastened on said sleeve, vand has its outer end connected to or engaged with a load carrying spring z' secured to the framework. of the vehicle.

From the foregoing construction it will be seen that any movements of the crankarms Z carrying the road wheels are communicat-ed to the crank-arms 7L on the sleeves b at the inner sides of the bearings f and thence to the springs z' and j. As each sleeve with its crank-arms CZ and 72, is free to move independently'in the bearings 7 and about the rod or tube a, (subject to the control of the springs z' and j), the vertical movement of one wheel will not affect the vertical movement of the other and companion Wheel.

Dealing now with the rear axle, Figures 3 and A, the construction follows the same general lines as with the front axle in so far as the sleeves b, crank-arms d carrying the road wheels, bearings and springs z" and j are concerned. As it is a diflicult matter for a rod or tube to be carried right through an axle having the usual type of rear drive employing worm or bevel gearing, the tubes a may be bolted on each side of the centre Worm or bevel casing c and the driving shaft Z may pass through the centres of the tubes a', the sleeves b working about the tubes and in the bearings 7E in the manner described above in connection with the front axle. For vehicles employing chain or shaft drive to each rear wheel a tube passing right through the axle may be used without diiiiculty. As the wheels have been removed from the usual direct line of drive some other and intermediate means must be em ployed to carry the drive to the wheels now mounted on stub axles m carried by the crank-arms d. A pair of spur gear Wheels n are shewn in the drawings, but chain drive or counter shaft drive may be used. If the pair of spur gear wheels are used the centre bevel or worm drive at ,7c must be arranged accordingly, otherwise the drive would be reversed. rlhe crank-arms h co-operating `with the springs z" and j may, if preferred,

be dispensed with, andthe springs be arranged to connect or engage direct with the crank-arms d carrying the road wheels.

The member o, shown at the inner ends of the sleeves o, o covers the joint between the sleeves Z9 of the front axle, Figures l and 2, or between the sleeves o and centre casing 7c of the rear axle, Figures 3 and il. The member may be fixed to a cross member of the chassis framework and be in the nature of a bracket or bearing, or it may be a simple covering sleeve, the object being, besides covering the joint, to form a bearing to support the axle. ln light cars the member 0 may be dispensed with.

The load carrying spring ,z" and the rebound or reaction springs j, j are anchored to the chassis or framework e by means of brackets ,09 r in any other suitable manner. rfhe gear wheel n secured to the drive shaft Z of Figures 3 and lmay form Apart of or be fixed to a brake drum.

From the above description it will be appreciated that each road wheel of the vehicle is sprung separately and can move independently in a vertical direction, and that unsp 'ung weight is reduced to the smallest possible amount. As the axles are carried in bearings lixed to the side members of the chassis or framework, and are unable to move in a vertical direction relatively to the chassis, improved mechanical efficiency is obtained au the rear axle is always kept in the same plane relatively to the gear box under every condition of load; universal joints are not called upon to correctV differences of alignment and may even be dis` pensed with: these advantages quite odset the possible slight loss of eiiciency in the introduction of an extra pair of gears'in the rear wheel drive. The effect of an extra long wheel base is secured. The vehicle will hold the road much better than thoseprovided with ordinary suspension, as one wheel passing over an obstacle does not alfectthe others: in passing over uneven surfaces the wheels adapt themselves to the contour of the road: the weight of the vehicle on the springs cannot produce a bouncing and rolling effect at speed as the axles are confined in the rigid bearings fixed to theframework of the chassis: this is a great improvement on the usual method of relying on the springs and shackle pins to resist rolling andl twisting strains. A lighter construction of chassis is possible as radius rod and tongue tubes are not required and axles may be made lighter as they can be supported in the centre. The wear of tyres is reduced to a minimum. The improved spring suspension is equally adaptable to all types of automobiles, from the high powered racing car to the lorry'and motor omnibus: with the former, higher Vspeeds will be possible owing to the better road holding qualities and consequent reduction 1n wheel spin, and with the latter greaterv steadiness and comfort in riding will be Y realized together with an appreciable reduci tion in cost of upkeep and repairs.

The foregoing constructions are capable of arms being arranged to engage with loadcarrying springs and the others for engaging with rebound springs. To secure efficient lubrication when av tube vis used to carry the sleeves, this tube may be fitted with lubricant and have small holes drilled inits walls to allow the lubricant to reach the sleeve bearings.

The relationship between the'lengths of the crank-arms may be such that the movement of a spring is less than. that of its corresponding wheel, or vice versa. Thus, if the crank-arm carrying a wheel is longer than the crank-arm engaging the corresponding spring or springs, the movement of the spring or springs would be less than the movement of the wheel. ln this manner the relative movement of a wheel and the spring or springsrcan be regulated by employing crank-arms ot' ditlierent lengths.

Vf hat I claim is l. A vehicle spring suspension system including a rear axle, an elongated sleeve mounted for 'free rotation on the axle for substantially halt the length of the latter,

bearings carried by the vehicle frame for supporting the respective ends of the sleeve, a cranl; arm connect-ed to the sleeve and supporting the wheels, a second cranlr arm connected to the sleeve and proj eeted therefrom in a direction substantially at right angles to the sleeve, a vehicle spring supporting means,

and a connection between said supporting meansy and the free end of the second Crank arm.

2. A vehicle spring suspension system including a rear axle, an elongated sleeve mounted for free rotation on the axle for substantially halt the length of the latter, bearings carried by the vehicle 'frame for supporting the respective ends of the sleeve, a crank arm connected to the sleeve, and supporting the Wheels, a second crank arm connected to the sleeve and projected therefrom in a direction substantially at rightangles to the sleeve, a vehicle spring supporting means including load springs and rebound springs of different strengths, and a connection between said supporting means and the t'ree end of the second crank arm.

In testimony whereof I have hereunto signed my name. f FRANKk SMEDLEY FARNSWORTH,

Certificate of Correction. n 927, to

Patent No. 1,633,933. Granted June 28, 1

FRANK SMEDLEY FARNSWORTH.

It is hereby certified that error appears in the printed specification of the abovenumbered patent requiring correction as follows: Page 3, lines 28 andv 42, claims 1 and 2, respectively, or a rear read an; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record o the oase in the Patent Office.

Signed and sealed this 23d day of August, A. D. 1927.

[SEALl M. J. MOORE,

Acting Oofrmnzssiomev' of Patents; 

